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“The path pursued by those who have no return is as follows:Fire, light, day-time, the bright fortnight, the six months of the northern solstice; following this path, men who know BRAHMAN go to BRAHMAN.

As contrasted with this path of no-return there is the path of sure-return which is explained in the following:Smoke, night-time, the dark fortnight, also six months of the southern solstice, attaining by these to the Moon, the lunar light, the “YOGI” returns.”

These are words from the Bhagavad Gita, a book on Hinduism. Those who have no return are those who have found Moksha, those who will unite with God (Brahman) Those who return are those who die, who go to heaven, and then return to Earth for yet another life (these are the Yogis). These are the two paths that the soul takes when it leaves the body – according to the Gita.
My mum has been reading the Gita. She stumbled upon these words, and told me to take a look.
And I just felt they were so mysterious….

Whether or not you believe in the afterlife and souls and paranormal activity (which I have to admit I find all quite intriguing), I’ll leave you with a clip on the solstices – it’s scientific, so wary not. I wasn’t quite sure myself what the solstices meant (the last time I studied these was back when I was 15 – and my mind has forgotten everything since, besides meeting Good Charlotte for autographs, and fist-knuckling Bill). So I did some reading. And it’s all quite easy actually. The earth moves around the sun in a plane, the Ecliptic.
But Earth’s rotational axis is tilted at 23.5 degrees. So that means, 6 months in a year, the northern hemisphere will have longer days than the south, and the next months, the southern hemisphere will take over. Solstices happen on the peak of these: The northern solstice when the sun is directly above the Tropic of Cancer (a latitude line). The longest day happens in the entire northern hemisphere happens then; and the longest night happens in the Southern hemisphere. And the southern solstice, when the longest day is in the Southern hemisphere (to be more specific, the Tropic of Capricorn); the longest night in the northern.

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Stumbled upon a really useful article on my Astronomy reader – written by the CuriousAstronomer…every “telescope-user-beginner” has got to read it! And voila, my first reblog! 😉
These are really the essentials you’ve got to know when collimating your scope. If you need to collimate the secondary mirror of a reflector, you’d need to adjust the bolts on the spider to get the mirror aligned to the focuser (you’d need a sighting tube for this)…but mostly you’d only need to adjust the primary (the rear) mirror – and for that, just tweak the screws on it, till you get an out-of-focus star that looks like a doughnut :)) (pic is below). Here as well, a sighting tube or a laser collimator come in handy (though they’re not altogether necessary).

Heyyy thanks Rhodri for posting this up – been great meeting you! — who knew the world was so small!

I was on the BBC last week recording an interview which will go out this week. One of the topics discussed (in addiition to how to take a pee in the dark) was how to collimate a telescope.

Two types of telescopes – Refracting and Reflecting

There are two basic types of telescopes, refracting telescopes (which use lenses) and reflecting telescopes (which use mirrors). Either type of telescope can become mis-aligned, usually through the telescope being knocked. Putting it back into alignment (technically called collimation) is not a difficult process, and should be the kind of thing anyone can do with a little patience.

There are many expensive gadgets available to help you align a telescope, but none of them is really necessary. The easiest way to do it is to simply point the telescope at a star and then de-focus the image. You will end up with a…

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After a year and a half of OptCorp and Cloudynight/Astronomyforum reviews, here’s what I’ve come up with.

My “Must Have” or rather ‘Futilely Desire” list:

1. A Barlow (would love a Televue 2″ 2x Powermate)
2. A Wide Field Eyepiece ( aVixen 1.25″ 40mm NLV seem like the best bet! – would love the 2″ 50mm, if not for the extra 100 dollars!)
3. A Devoted Planetary Eyepiece (William Optics anyone?)
4.A Stellarvue (yes you heard it!) 10x60mm Finderscope – that’d also serve as a mini portable refractor for the planets, with its 2″ focuser, and 1.25″ adapter.
5. A pair of binoculars (less than 70mm aperture, so I wouldnt need a tripod) ….or should I get a monocular? Waterproofing is great as well! Any recommendations?
6. A Baader Planetarium Moon & SkyGlow filter.

And yes, you must know my scope and viewing conditions.
I have a 10″ Dobsonian Skywatcher.
And the basic set of accessories that come with it, a 24mm and a 10mm Plossl.
Heavy light pollution and haze from my side. Viewing is mostly limited to planets.
But occasionally the skies are clear – and I get to catch the brighter nebular. Still a dream of mine to catch the Horsehead Nebula someday.
Thinking of getting a wild-field eyepiece to starhop. Do you think it’ll work? There really isn’t much point in starhopping with a finderscope, as the stars are too dim from where I’m at.

So let me know what’s your favourite pick? And if you’ve got any other suggestions, that’ll be great!

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It started off with mum and I watching the floods brought by Sandy on CNN and mum asked what’s the cause for waves. Well wind caused Sandy’s waves. But, Daily tides, high and low, are caused by the moon.

The accepted theory is the moon exerts a force of gravity on earth as the moon rotates earth (both the moon and earth rotate counter clockwise, but earth’s rotation is much faster). The parts of earth passed by the moon are pulled towards the moon, and when water is pulled, tides are formed! Yayy! Sounds easy right.

– with the theory that the moon pulls the side closest to it the most, pulls the middle of the Earth with a medium force and the side furthest away with the least force. So the bulge of water on the left of the pic is pulled the least, appearing as a bulge as Earth is moved towards the right.

The sun comes into the picture as well, also exerting a pull on water. But, the moon’s pull beats the sun. Though the suns is massive, it’s too far away (F=GMm/r2, Newton’s Law of Gravitation) And if the moon and sun are on opposite directions to Earth, high tides become lower.

But then again, if the moon pulls pulls parts of Earth with different distances from it with different forces, each part would have a different acceleration. F=ma. The parts closest to the moon would accelerate the most (in the pic above, it would be the right end of Earth) and the opposite end (the left), the least. And so, with one end gaining acceleration compared to the other, Earth would be stretched and eventually pulled apart.

So, there has to be a restraining force. Earth’s gravity and its tension? Or a centrifugal force? Now what about a centripetal force?

And then there’s the belief that tides don’t form on the equator. But I’ve seen it for myself, they do form! In fact, they’re semidiurnal tides (two equal high tides and low tides in a day). One high tide on each of the pair of “bulges” created. Check out ocean motion. to find out about types of tides at different latitudes on Earth.

I’ll keep you updated on tides once I piece everything together (and find some missing links, like I’m sure the moon’s orbit around Earth at at about a 5 degree angle to Earth’s ecliptic would have an effect as well). Let me know if you’ve got any ideas of your own!

And mum has two questions of her own:
1. Why isn’t paper pulled towards the moon when its so light.
To me, it is, but the effect is so small that you’ll never realize it.
2. Why do you get the highest tides on the full moon. This, I don’t know. So let me know if you do pleaseee.

Our stargazing night to catch Saturn! Sometime around mid this year I believe. And we had late night park-walkers joining in! The clouds were coming in and we were keeping our fingers crossed. And we were lucky to catch Saturn in time! It was the first sight of the beautiful planet – its rings and the Cassini Division – for many of us, including myself! And when the clouds rolled in, we packed up and headed off for some seriously unhealthy but the sweetest supper: “Roti Tissue”, paper thin pancakes cooked with a layer of condensed milk. Sounds good right.

One mystery though…Some of them said Saturn looked white, but to me, it was orange….

This is what I see when I take my telescope out to the balcony to stargaze.

September – November 2011: Jupiter lies vertical to where I’m standing.

January – March 2012: Mars rises from the horizon and eventually rises to be vertical to my star gazing spot mostly.

Mid March 2012: Saturn rises vertically above me too!

So, Earth and all these planets orbit the Sun in their respective elliptical orbits arranged in concentric layers. And if these planets rise to be vertically above me, my home, my body, my telescope are pointed straight at those planets. That means, we are all aligned in a straight line.

How awesome is that! Plus by observing the night sky straight up (vertically), I get the clearest view of the planets as the atmospheric layers would be thinnest and hence, light entering my telescope would be less scattered. Yay!

What about you? Do you live right on the equatorial line too?

ps. This is a hypothesis created by me. It may be wrong. If it is, let me know.